Have you ever questioned whether explaining grammar is effective use of class time? Of course you have, this is one of the big points addressed in the communicative approach!
For younger levels, an inductive way of exposing students to grammar is so effective and really compliments grammar knowledge they might see in a table or which has been drilled into them at school. When it comes down to the more complicated and stylistic points of grammar, say, inversion for example, sure you can show students a few examples in a text (any more and that would be extremely artificial!), but then what? And then you have the issue that not only does explanation take a long time, but also setting these into a communicative setting is quite difficult. So, the last recourse is explain and drill.
But what if your explanation, very declarative, straightforward and traditional, were done at home? This is what the flipped classroom aims to do. Give declarative information, material that would normally be lectured at home. Homework, drills, etc. can then be done in class. Flipping learning has been a huge success in science and mathematics because it also allows for students to have access to additional resources because declarative knowledge being explained is linked to online resources. And students can stop, pause and rewind at random.
For language, perhaps this is not so clear and so what I am doing in 2014-15 is trying to at least “tilt” my classroom. Through Moodle, I am proving links to grammar tutorials, then students do the standard course book exercises. The next class we correct those exercises and then do freer types of practice, ironing out points they might not have understood so well. More importantly, we try to integrate this grammar into realistic contexts into the classroom, moving past analyzing language and into using it. For example lessons (these are my first attempts, done simply, in just a few minutes after preparing the materials).
For more information on this type of teaching, which won’t replace us as teachers, but merely underline our importance and free up opportunities for communicating and interesting classroom work: http://flippedclassroom.org